Mid-limb cam crossbow system

ABSTRACT

Provided is a mid-limb cam crossbow system comprising a beam; a bow assembly having a first bow limb of length L1 and second bow limb of length L2; a first cam engaged with the first bow limb at a point between (0.15)L1 and (0.75)L1 from the limb end; a second cam engaged with the second bow limb at a point between (0.15)L2 and (0.75)L2 from the limb end; a first power string engaged with the first cam and a region on the second bow limb greater than (0.75)L2 from the limb end; a second power string engaged with the second cam and a region on the first bow limb greater than (0.75)L1 from the limb end; and a bowstring engaged between the first cam and the second cam. The bow assembly may be configured in an uncocked configuration or a cocked configuration. L1 and L2 are between 15 centimeters and 65 centimeters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/446,035, filed Jan. 13, 2017, the entirety of each of which are fullyincorporated by reference herein.

BACKGROUND

The present subject matter is directed to apparatuses and methodsregarding crossbows. More specifically the present subject matter isdirected to apparatuses and methods for a crossbow having one or camssupported along a limb offset from either end of the limb.

Crossbows have been used for many years as a weapon for hunting andfishing, and for target shooting. Typically, a crossbow may include abeam including a stock member and a barrel connected to the stockmember. The barrel typically has an arrow receiving area for receivingan arrow to be shot. The crossbow may also include a bow assemblysupported on the main beam that includes a bow and a bowstring connectedto the bow for use in shooting arrows. A trigger mechanism, alsosupported on the main beam, holds the bowstring in a drawn or cockedcondition and can thereafter be operated to release the bowstring out ofthe uncocked condition to shoot the arrow.

The configuration of the bow and bowstring strongly influence the energystorage capacity of the bow and the energy and power output of thecrossbows. It remains desirable to produce a compact bow havingsufficient energy storage capacity, energy and power output, and otherdefining operational characteristics.

SUMMARY

Provided is a mid-limb cam crossbow system comprising a beam; a bowassembly having a first bow limb of length L1 and second bow limb oflength L2; a first cam engaged with the first bow limb at a pointbetween (0.15)L1 and (0.75)L1 from the limb end; a second cam engagedwith the second bow limb at a point between (0.15)L2 and (0.75)L2 fromthe limb end; a first power string engaged with the first cam and aregion on the second bow limb greater than (0.75)L2 from the limb end; asecond power string engaged with the second cam and a region on thefirst bow limb greater than (0.75)L1 from the limb end; and a bowstringengaged between the first cam and the second cam. The bow assembly maybe configured in an uncocked configuration or a cocked configuration. L1and L2 are between 15 centimeters and 65 centimeters.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangement ofparts, embodiments of which will be described in detail in thisspecification and illustrated in the accompanying drawings which form apart hereof and wherein:

FIG. 1 is a top view of one embodiment of a crossbow comprising amid-limb cam crossbow system.

FIG. 2 is another top view of the embodiment of FIG. 1 of a crossbowcomprising a mid-limb cam crossbow system.

FIG. 3 is another top view of the embodiment of FIG. 1 of a crossbowcomprising a mid-limb cam crossbow system.

DETAILED DESCRIPTION

Referring now to the drawings wherein the showings are for purposes ofillustrating embodiments of the present subject matter only and not forpurposes of limiting the same, and wherein like reference numerals areunderstood to refer to like components, provided is a mid-limb camcrossbow system and a method for using same.

In a first embodiment, a mid-limb cam crossbow system 100 may comprise abeam 110 and a bow assembly 140.

In the first embodiment, the beam 110 may be elongated. The beam 110 mayinclude a stock member 112, and a barrel 114. The barrel 114 may beconnected to the stock member 112. The barrel 114 may have an arrowreceiver region 116 adapted to receive an associated arrow (not shown).The beam 110 may have a first beam end 117 and a second beam end 118opposite the first beam end 117.

The bow assembly bow assembly 140 is mounted to the beam 110 at thefirst beam end 117. The bow assembly 140 may comprise a riser 142engaged with the barrel 114. The riser 142 may operatively engage both afirst limb assembly 150, and a second limb assembly 160, to the beam110. The bow assembly 140 may further comprise a first power cord 146, asecond power cord 148, and a bow string 144.

The first limb assembly 150 comprises an elongated first limb 151defining a first end 152 and a second end 155 offset from the first end152 by the length L1 of the elongated first limb 151. The first limbassembly 150 is rotatably engaged to the riser 142 at a first axis 154proximate to the first end 152. The first end 152, may also be referredto herein as the proximate end 152 of the first limb 151. The first limbassembly 150 further comprises a first power cord mount 158. The firstlimb assembly 150 further comprises a first cam 156 rotatably engagedwith the first limb 151 at a first cam mount point 159 between the firstaxis 154 and the first power cord mount 158 and substantially offsetfrom each. In some embodiments the first cam 156 is rotatably engagedwith the first limb 151 at a first cam mount point 159 midway betweenthe first axis 154 and the first power cord mount 158. In someembodiments, the first cam 156 is rotatably engaged with the first limb151 at a first cam mount point 159 offset from the proximate end 152 ofthe first limb by a length between (0.15)L1 and (0.75)L1.

The second limb assembly 160 comprises an elongated second limb 161defining a first end 162 and a second end 165 offset from the first end162 by the length L2 of the elongated second limb 161. The second limbassembly 160 is rotatably engaged to the riser 142 at a second axis 164proximate to the first end 162. The first end 162, may also be referredto herein as the proximate end 162 of the second limb 161. The secondlimb assembly 160 further comprises a second power cord mount 168. Thefirst limb assembly 160 further comprises a second cam 166 rotatablyengaged with the second limb 161 at a second cam mount point 169 betweenthe second axis 164 and the second power cord mount 168 andsubstantially offset from each. In some embodiments, the second cam 166is rotatably engaged with the second limb 161 at a second cam mountpoint 169 offset from the proximate end 162 of the second limb by alength between (0.15)L2 and (0.75)L2.

The bow string 144 may be operatively engaged between the first cam 156and the second cam 166. The first power cord 146 may be operativelyengaged between the first power cord mount 158 and the second cam 166.The second power cord 148 may be operatively engaged between the secondpower cord mount 168 and the first cam 156. The bow limbs 151, 161define opposite ends of the bow assembly 140. In some embodiments, thefirst power cord mount 158 is offset from the proximate end of the firstlimb 152 by a length of greater than (0.75)L1. In some embodiments, thesecond power cord mount 168 is offset from the proximate end of thesecond limb 162 by a length of greater than (0.75)L2.

Location of the first cam 156 between the first axis 154 and the firstpower cord mount 158, or location of the second cam 166 between thesecond axis 164 and the second power cord mount 168 may permit thedesigner additional latitude in providing desirable performance, sizeand weight.

Numerous embodiments have been described, hereinabove. It will beapparent to those skilled in the art that the above methods andapparatuses may incorporate changes and modifications without departingfrom the general scope of the present subject matter. It is intended toinclude all such modifications and alterations in so far as they comewithin the scope of the appended claims or the equivalents thereof.

We claim:
 1. A mid-limb cam crossbow system 100 comprising: an elongatedbeam 110 having a first beam end 117, and a second beam end 118 oppositethe first beam end 117; a bow assembly 140 mounted to the beam 110 atthe first beam end 117, the bow assembly 140 having a pair of limbs 151,161 defining opposite ends of said bow assembly 140, the pair of limbs151, 161 being a first limb 151 and a second limb 161, wherein the firstlimb 151 has a proximate end 152 and a distal end 155 offset from theproximate end 152 by a length L1, and the second limb 161 has aproximate end 162 and a distal end 165 offset from the proximate end 162by a length L2; a first cam 156 rotatably engaged with the first limb151 at a first cam mount point 159 offset from the proximate end of thefirst limb 152 by a length between (0.15)L1 and (0.75)L1; a second camrotatably engaged with the second limb at a second cam mount point 169offset from the proximate end of the second limb 162 by a length between(0.15)L2 and (0.75)L2; a first power cord 146 operatively engagedbetween a first power cord mount 158 and the second cam 166, wherein thefirst power cord mount 158 is offset from the proximate end of the firstlimb 152 by a length of greater than (0.75)L1; a second power cord 144operatively engaged between a second power cord mount 168 and the firstcam 156, wherein the second power cord mount 168 is offset from theproximate end of the second limb 162 by a length of greater than(0.75)L2; a bow string adapted to propel an arrow, the bowstringoperatively engaged between the first cam and the second cam; andwherein the bow assembly may be configured in a) an uncockedconfiguration in which, i) the bow assembly stores some residual energy,ii) the bowstring is located at a uncocked bowstring position along themain beam; or b) a cocked configuration in which, i) the bow assemblystores more than 75 foot pounds of energy greater than the residualenergy, ii) the bowstring is located at a cocked bowstring positionalong the main beam which is more than 20 centimeters from the uncockedbowstring position; and wherein L1 is between 15 centimeters and 65centimeters, and L2 is between 15 centimeters and 65 centimeters.
 2. Themid-limb cam crossbow system of claim 1, wherein L1 is between 25centimeters and 55 centimeters, and L2 is between 25 centimeters and 55centimeters; wherein, in the cocked configuration, the bow assemblystores more than 95 foot pounds of energy greater than the residualenergy; and wherein the cocked bowstring position along the main beamwhich is more than 25 centimeters from the uncocked bowstring position.3. The mid-limb cam crossbow system of claim 2, wherein the first pivotpoint is offset from the proximate end of the first bow limb by a lengthbetween (0.30)L1 and (0.70)L1; and wherein the second pivot point isoffset from the proximate end of the second bow limb by a length between(0.30)L2 and (0.70)L2.
 4. The mid-limb cam crossbow system of claim 3,wherein the first power string is operatively engaged between the firstcam and a region on the second bow limb offset from the proximate end ofthe second bow limb by a length of greater than (0.80)L2; and whereinthe second power string is operatively engaged between the second camand a region on the first bow limb offset from the proximate end of thefirst bow limb by a length of greater than (0.80)L1.
 5. The mid-limb camcrossbow system of claim 1, wherein L1 is between 35 centimeters and 45centimeters, and L2 is between 35 centimeters and 45 centimeters;wherein, in the cocked configuration, the bow assembly stores more than115 foot pounds of energy greater than the residual energy; and whereinthe cocked bowstring position along the main beam which is more than 30centimeters from the uncocked bowstring position.
 6. The mid-limb camcrossbow system of claim 5, wherein the first pivot point is offset fromthe proximate end of the first bow limb by a length between (0.4)L1 and(0.6)L1; and wherein the second pivot point is offset from the proximateend of the second bow limb by a length between (0.4)L2 and (0.6)L2. 7.The mid-limb cam crossbow system of claim 6, wherein the first powerstring is operatively engaged between the first cam and a region on thesecond bow limb offset from the proximate end of the second bow limb bya length of greater than (0.85)L2; and wherein the second power stringis operatively engaged between the second cam and a region on the firstbow limb offset from the proximate end of the first bow limb by a lengthof greater than (0.85)L1.
 8. The mid-limb cam crossbow system of claim1, wherein L1 is between 30 centimeters and 40 centimeters, and L2 isbetween 30 centimeters and 40 centimeters; wherein, in the cockedconfiguration, the bow assembly stores more than 135 foot pounds ofenergy greater than the residual energy; and wherein the cockedbowstring position along the main beam which is more than 40 centimetersfrom the uncocked bowstring position; wherein a second angle is definedby a vector along the uncocked bowstring position, and a vector alongthe first power string in the uncocked configuration; and wherein thesecond angle is between 0 and 30 degrees.
 9. The mid-limb cam crossbowsystem of claim 8, wherein the first pivot point is offset from theproximate end of the first bow limb by a length between (0.45)L1 and(0.55)L1; and wherein the second pivot point is offset from theproximate end of the second bow limb by a length between (0.45)L2 and(0.55)L2.
 10. The mid-limb cam crossbow system of claim 9, wherein thefirst power string is operatively engaged between the first cam and aregion on the second bow limb offset from the proximate end of thesecond bow limb by a length of greater than (0.90)L2; and wherein thesecond power string is operatively engaged between the second cam and aregion on the first bow limb offset from the proximate end of the firstbow limb by a length of greater than (0.90)L1.
 11. A method of using amid-limb cam crossbow system comprising: providing a mid-limb camcrossbow system having an elongated main beam having a first beam end,and a second beam end opposite the first beam end, a bow assemblymounted to the main beam at the first beam end, the bow assembly havinga pair of bow limbs defining opposite ends of said bow assembly, thepair of bow limbs being a first bow limb and a second bow limb, whereinthe first bow limb has a proximate end and a distal end offset from theproximate end by a length L1, and the second bow limb has a proximateend and a distal end offset from the proximate end by a length L2, afirst cam rotatably engaged with the first bow limb at a first pivotpoint offset from the proximate end of the first bow limb by a lengthbetween (0.15)L1 and (0.75)L1; a second cam rotatably engaged with thesecond bow limb at a second pivot point offset from the proximate end ofthe second bow limb by a length between (0.15)L2 and (0.75)L2, a firstpower string operatively engaged between the first cam and a region onthe second bow limb offset from the proximate end of the second bow limbby a length of greater than (0.75)L2, a second power string operativelyengaged between the second cam and a region on the first bow limb offsetfrom the proximate end of the first bow limb by a length of greater than(0.75)L1, a bowstring adapted to propel an arrow, the bowstringoperatively engaged between the first cam and the second cam, andwherein the bow assembly may be configured in a) an uncockedconfiguration in which, i) the bow assembly stores some residual energy,ii) the bowstring is located at a uncocked bowstring position along themain beam, or b) a cocked configuration in which, i) the bow assemblystores more than 75 foot pounds of energy greater than the residualenergy, ii) the bowstring is located at a cocked bowstring positionalong the main beam which is more than 20 centimeters from the uncockedbowstring position, and wherein L1 is between 15 centimeters and 65centimeters, and L2 is between 15 centimeters and 65 centimeters;changing the bow assembly from a uncocked configuration to a cockedconfiguration by an operation comprising the steps of a) moving thebowstring from the uncocked bowstring position to the cocked bowstringposition, and b) storing energy in the bow assembly of more than 75 footpounds of energy greater than the residual energy.
 12. The method ofusing a mid-limb cam crossbow system of claim 11, wherein L1 is between25 centimeters and 55 centimeters, and L2 is between 25 centimeters and55 centimeters; wherein, in the cocked configuration, the bow assemblystores more than 95 foot pounds of energy greater than the residualenergy; and wherein the cocked bowstring position along the main beamwhich is more than 25 centimeters from the uncocked bowstring position.13. The method of using a mid-limb cam crossbow system of claim 12,wherein the first pivot point is offset from the proximate end of thefirst bow limb by a length between (0.30)L1 and (0.70)L1; and whereinthe second pivot point is offset from the proximate end of the secondbow limb by a length between (0.30)L2 and (0.70)L2.
 14. The method ofusing a mid-limb cam crossbow system of claim 13, wherein the firstpower string is operatively engaged between the first cam and a regionon the second bow limb offset from the proximate end of the second bowlimb by a length of greater than (0.80)L2; and wherein the second powerstring is operatively engaged between the second cam and a region on thefirst bow limb offset from the proximate end of the first bow limb by alength of greater than (0.80)L1.
 15. The method of using a mid-limb camcrossbow system of claim 11, wherein L1 is between 30 centimeters and 40centimeters, and L2 is between 30 centimeters and 40 centimeters;wherein, in the cocked configuration, the bow assembly stores more than135 foot pounds of energy greater than the residual energy; and whereinthe cocked bowstring position along the main beam which is more than 40centimeters from the uncocked bowstring position.
 16. The method ofusing a mid-limb cam crossbow system of claim 15, wherein the firstpivot point is offset from the proximate end of the first bow limb by alength between (0.45)L1 and (0.55)L1; and wherein the second pivot pointis offset from the proximate end of the second bow limb by a lengthbetween (0.45)L2 and (0.55)L2.
 17. The method of using a mid-limb camcrossbow system of claim 16, wherein the first power string isoperatively engaged between the first cam and a region on the second bowlimb offset from the proximate end of the second bow limb by a length ofgreater than (0.90)L2; and wherein the second power string isoperatively engaged between the second cam and a region on the first bowlimb offset from the proximate end of the first bow limb by a length ofgreater than (0.90)L1.
 18. The method of using a mid-limb cam crossbowsystem of claim 17, wherein a second angle is defined by a vector alongthe uncocked bowstring position, and a vector along the first powerstring in the uncocked configuration; wherein the second angle isbetween 0 and 30 degrees.
 19. A mid-limb cam crossbow system comprising:an elongated main beam having a first beam end, and a second beam endopposite the first beam end; a bow assembly mounted to the main beam atthe first beam end, the bow assembly having a pair of bow limbs definingopposite ends of said bow assembly, the pair of bow limbs being a firstbow limb and a second bow limb, wherein the first bow limb has aproximate end and a distal end offset from the proximate end by a lengthL1, and the second bow limb has a proximate end and a distal end offsetfrom the proximate end by a length L2; a first cam rotatably engagedwith the first bow limb at a first pivot point offset from the proximateend of the first bow limb by a length between (0.45)L1 and (0.55)L1; asecond cam rotatably engaged with the second bow limb at a second pivotpoint offset from the proximate end of the second bow limb by a lengthbetween (0.45)L2 and (0.55)L2; a first power string operatively engagedbetween the first cam and a region on the second bow limb offset fromthe proximate end of the second bow limb by a length of greater than(0.90)L2; a second power string operatively engaged between the secondcam and a region on the first bow limb offset from the proximate end ofthe first bow limb by a length of greater than (0.90)L1; a bowstringadapted to propel an arrow, the bowstring operatively engaged betweenthe first cam and the second cam; and wherein the bow assembly may beconfigured in a) an uncocked configuration in which, i) the bow assemblystores some residual energy, ii) the bowstring is located at a uncockedbowstring position along the main beam; or b) a cocked configuration inwhich, i) the bow assembly stores more than 135 foot pounds of energygreater than the residual energy, ii) the bowstring is located at acocked bowstring position along the main beam which is more than 40centimeters from the uncocked bowstring position; and wherein L1 isbetween 32 centimeters and 38 centimeters, and L2 is between 32centimeters and 38 centimeter; wherein a second angle is defined by avector along the uncocked bowstring position, and a vector along thefirst power string in the uncocked configuration; and wherein the secondangle is between 15 and 30 degrees.
 20. The mid-limb cam crossbow systemof claim 19 wherein, L1 differs from L2 by at least 3 centimeters.